Rail car slipper

ABSTRACT

An assemblage of frame, sliding shoes, control springs and control elements for bearing the weight of a car sliding on rails and for guiding and stabilizing the car on the rails.

o thine States awn 1 [111 3,791,307

Applegate Feb. 12, 1974 [5 RAHL CAR SUPPER 3,330,222 7/1967 Sonnenburg 104 134 Inventor: L ndsay M. ppflegme, Paradise, 454,307 6/189] Tobey 104/134 Calif.

[73] Assignee: Cushion Rail international, Inc., Primary Examiner-Gerald M. Forlenza Roseville, Calif. Assistant ExaminerD. W. Keen [22] Filed: Apr. 3, 1972 [21] Appl. N0.: 240,744

[57] ABSTRACT [52] US. Cl. 104/134 [51] Int. Cl A63g 21/00 An assemblage of frame, sliding shoe Control p g [58] Field of Search 104/134, 135; 188/43, 44 and control elements for bearing the weight of a car sliding on rails and for guiding and stabilizing the car [5 6] References Cited on the rails.

UNITED STATES PATENTS 2,724,966 11/1955 Northrop 104/134 2 Claims, 2 Drawing Figures PATENTED FEB 1 2:974 v 3,791,307

sum 1 or 2 FIGURE RAIL CAR SLIPPER This invention is concerned with high speed rail travel, particularly at those speeds where wheels are regarded as impracticable. Sliding shoes, known in this art as slippers, have been used experimentally for testing rocket-propelled vehicles at speeds to and exceeding sonic velocities.

A principle object of this invention is to provide a slipper that can be used for routine operation at speeds in the range of 500 to 1,000 kilometers per hour. A second object is to provide, in the slipper, mechanism to assist in the control of effective loading of the slipper, such as described in my copending application for US. Pat. No. 130,926, now U.S. Pat. No. 3,721,198. Another object is to provide means for stabilizing vehicular travel, limiting vertical and lateral vibration and oscillation.

What constitutes my present invention is described in the following specification with reference to the accompanying FIGS. 1 and 2, and is succinctly defined in the appended claims.

1n the drawing, F 10. l is a half-sectional view cut parallel to the rail in the direction of travel showing the slipper in position on the rail 1 shown in outline. FIG. 2 shows the slipper and rail 1 in cross section.

In FIGS. 1 and 2, supported on the rail 1, a slipper bearing and sliding member 2, referred to as a shoe, constitutes the principal bearing surface sliding on the rail. This shoe and others to be described are removable for replacement when worn in service. A second shoe, 3, shown in side view inFlG. '1 and in cross section in FIG. 2, is in contact with the side of the rail. A third shoe 4,' shown in side view in FIG. 1 and in cross section in F1G..-2, is in contact with the under side of the head, or bearing surface, of the rail. These bearing shoes, 2, 3, and 4 are held in a frame 5 in which bearing springs 6, 7 and 8 provide a degree of flexibility between frame 5 which is loaded at pivot connection 11 and shoes 2, 3 and 4 while applying pressure thereon, respectively.

Springs 6 and 7 are parallelled respectively by hydraulic damping cylinders 9 and 10. These hydraulic dampers absorb energy of shock and oscillation imposed on the springs and stabilize the travel of the slipper on the rail, minimizing vertical and lateral oscillation in respect to shoes 2 and 4 vertically and shoes 3 laterally.

At selected places on frame 5, transducing devices 12 for responding to spring displacement and for producing electrical or mechanical signals as functions of spring displacement are associated with spring mountings l3 and transducer housings 14. Vertical transducers 12 in housings 14 associated with spring housing 13 are shown in FIG. 1 at two intermediate locations of vertical springs 6. Similarly, transducers 12 in housings 14 are shown at locations associated with lateral springs 7. The vertical transducers are provided as control transducers for controlling vertical loading on springs 6 as prescribed in my copending application for US. Pat. No. 130,926. A slipper of the kind shown here would wear excessively and also generate excessive heat resulting from frictional resistance on the rail unless the vertical load on shoe 2 could be limited to. values consistent with reasonable friction load and resulting loss of energy. This slipper being provided with means 9 and 10 for clamping oscillation, and with transducers 12 for participating in control of vertical loading, is adaptable to use with systems where vertical loading can be limited to magnitudes appropriate to practicable frictional and heating limits. Transducers 12 may be of any type desired such as electricpotentiometers whose resistances vary as functions of spring displacement or hydraulic valves that open one channel for large spring displacements, close at a lesser displacement and open a second channel at still less displacement. Such valves are known in hydraulic control arts. Similarly simple electrical contacts, one contact closing for maximum, another contact for minimum, and both open for optimum spring displacement can be employed. Double-contact devices for reversibility control also are known in the controlling arts.

The slipper described herein is differentiated from the prior art by the springs and devices for control of vertical and lateral vibration and oscillation. Further differentiation is provided by the transducers paralleling the springs. The slippers of the prior art have been restricted to test conditions in which the slipper flexibility could be limited to that required for accommodation of track irregularities. The slipper described herein, however, is provided with a degree of flexibility, damping, capability of adjustment to varying load and track conditions, and to participation in control of imposed loading by meanssubject to precise design and calibration.

I claim:

1. In a rail-car slipper, the combination of a frame, shoes for sliding on a rail and spring situated between said frame and said shoes arranged to stabilize vertical and lateral contact of said shoes on said rail, said springs for vertical and lateral stabilization being mechanically paralleled by hydraulic damping devices, whereby mechanical and lateral displacement and oscillation are controlled in movement of said frame relative to said rail.

2. The combination as in claim 1 in which transducers are placed mechanically in parallel with said vertical springs to provide signals in proportion to the displacement of said vertical springs whose displacement is proportional to vertical loading, whereby said signals are made available for control of said vertical loading on said springs. 

1. In a rail-car slipper, the combination of a frame, shoes for sliding on a rail and spring situated between said frame and said shoes arranged to stabilize vertical and lateral contact of said shoes on said rail, said springs for vertical and lateral stabilization being mechanically paralleled by hydraulic damping devices, whereby mechanical and lateral displacement and oscillation are controlled in movement of said frame relative to said rail.
 2. The combination as in claim 1 in which transducers are placed mechanically in parallel with said vertical springs to provide signals in proportion to the displacement of said vertical springs whose displacement is proportional to vertical loading, whereby said signals are made available for control of said vertical loading on said springs. 